gstreamer/gst/avi
Julien Moutte c74043423e gst/: First batch implementing audio and video codec tags in demuxers.
Original commit message from CVS:
2004-02-23  Julien MOUTTE  <julien@moutte.net>

* gst-libs/gst/riff/riff-media.c: (gst_riff_create_video_caps),
(gst_riff_create_audio_caps), (gst_riff_create_iavs_caps),
(gst_riff_create_video_template_caps),
(gst_riff_create_audio_template_caps),
(gst_riff_create_iavs_template_caps):
* gst-libs/gst/riff/riff-media.h:
* gst/asfdemux/gstasfdemux.c: (gst_asf_demux_base_init),
(gst_asf_demux_audio_caps), (gst_asf_demux_add_audio_stream),
(gst_asf_demux_video_caps), (gst_asf_demux_add_video_stream):
* gst/avi/gstavidemux.c: (gst_avi_demux_add_stream):
* gst/matroska/matroska-demux.c: (gst_matroska_demux_add_stream),
(gst_matroska_demux_video_caps), (gst_matroska_demux_audio_caps),
(gst_matroska_demux_plugin_init): First batch implementing audio and
video codec tags in demuxers.
2004-02-23 22:16:21 +00:00
..
.gitignore Initial revision 2001-12-22 23:22:30 +00:00
avi-ids.h Riff, EBML, fourcc etc. work. Not fully finished, but better than what we used to have and definately worth a first b... 2003-12-07 20:00:41 +00:00
gstavi.c remove textdomain calls 2004-02-02 22:25:38 +00:00
gstavidecoder.c api change 2002-10-02 08:05:23 +00:00
gstavidemux.c gst/: First batch implementing audio and video codec tags in demuxers. 2004-02-23 22:16:21 +00:00
gstavidemux.h configure.ac: Fix configure check for mpeg2enc. We need 1.6.1.93 instead of 1.6.1.92, since the pkg-config file of 1.... 2004-01-01 22:45:57 +00:00
gstavimux.c change NULL to (NULL) for GST_ELEMENT_ERROR 2004-02-02 17:23:33 +00:00
gstavimux.h Riff, EBML, fourcc etc. work. Not fully finished, but better than what we used to have and definately worth a first b... 2003-12-07 20:00:41 +00:00
Makefile.am Riff, EBML, fourcc etc. work. Not fully finished, but better than what we used to have and definately worth a first b... 2003-12-07 20:00:41 +00:00
README Change everyone to video/x-msvideo 2003-11-27 21:49:39 +00:00

The avi decoder plugins 
-----------------------

The avi decoder consists of a set of gstreamer plugins:

 - demuxer (avidemux)
 - avi to gstreamer type converter (avitypes)
 - windows dlls wrappers.

the avidecoder element uses the above plugins to perform the avi
decoding. It is constructed as a custom bin which initially only has
the demuxer element in it. The demuxer has a set of padtemplates for
raw audio and video.

  (------------------------------------)
  ! avidecoder                         !
  !                                 (video/raw)...
  !     (----------)                   !
  !     ! demuxer (video/x-msvideo, auds)..
  !     !          !                   !
  !   -src         !                   !
  !  /  !         (video/x-msvideo, vids)..
 - src  !          !                   !
  !     (----------)                (audio/raw)...
  !                                    !
  (------------------------------------)

the demuxer has a set of padtemplates for the raw avi header properties.

The avi decoder will act on the new_pad signal of the demuxer element
and will attach an avitype plugin to the new pad. Caps negotiation will
convert the raw avi caps to the gstreamer caps. If the src pad of the
avitypes plugin are compatible with the avidecoder padtemplate, the 
avitype pad is ghosted to the avidecoder bin, this is the case where no
codec is needed (for raw PCM samples, for example).

When the avitypes caps are not compatible with one of the avidecoder 
templates, a static autoplugger is used the find an element to connect
the demuxers pad to the decoders padtemplate.

When no element could be found, an windec plugin is attached to the 
demuxers pad and the avitypes plugin is removed from the decoder.


example:
--------

 An avidecoder that has a video pad (decoded with windows dlls) and an
 audio pad (raw PCM).

  (----------------------------------------------------------------)
  ! avidecoder               (--------)    (------)                !
  !                          !avitypes!    !windec!       /-- (video/raw)
  !     (----------)     /-sink      src--sink   src -----         !
  !     !demuxer (video/x-msvideo,    !    !      !                !
  !     !          ! auds).. (--------)    (------)                !  
  !   -sink        !         (--------)                            !
  !  /  !        (video/x-..,!avitypes!                            !
 -sink  !          ! vids).. !        !                            !
  !     (----------)     \-sink      src -------------------- (audio/raw)
  !                          (--------)                            !
  (----------------------------------------------------------------)



TODO
----

automatically generate the padtemplates from all possible avi types
found in the registry.